Coprophagia is a standard, regular practice among carnivores in the wild, it's mentioned as a routine habit in general entries for "carnivore". There are various explanations offered:- 1) that carnivores use the faeces to mask their scent or because of extreme famine or 2):-" Many carnivores also eat herbivore dung, presumably to obtain essential nutrients that they could not otherwise obtain, since their dentition and digestive system do not permit efficient processing of vegetable matter."
The "extreme famine" reason, which I cited myself, doesn't explain "a standard, regular practice." The scent-masking, nutrient-deficiency, prey location, and bacterial supplementation reasons would explain a regular practice. However, the nutrient deficiency explanation (the need to eat partially processed vegetable matter to obtain unspecified nutrients or fiber) doesn't make sense, because wolves discard the partially-digested vegetable matter contents of rumens:
"Wolves usually tear into the body cavity of large prey and pull out and consume the larger internal organs, such as lungs, heart, and liver. The large rumen (weighing about 60 kg or 132 pounds for a moose) is usually punctured during removal and its contents spilled. The vegetation in the intestinal tract is of no interest to wolves, but the stomach lining and intestinal wall are consumed and their contents further strewn about the kill site." (Wolves: behavior, ecology, and conservation, by L. David Mech, Luigi Boitani, 2003)
Wolves will even laboriously nibble away at a frozen stomach to avoid ingesting its contents: "If the stomach of a large prey animal freezes before wolves find the carcass (e.g., if it died from starvation, accident, or earlier wounding by wolves), the wolves commonly consumed the entire stomach wall by laborious nibbling with their incisors." (Mech and Boitani, 2003)
"while coprophagia is a regular practice among carnivores, it may not be as essential to life as it is for herbivores."
It's definitely less essential to survival for carnivores, but I can't find any research indicating that it's even a normal, regular practice for wild carnivores who are eating a diet with sufficient nutrients and calories. There is tons of info on the Web re: coprophagia among wild herbivores and domesticated dogs (who eat deficient diets containing foods they are not designed to eat, like grains and soy), but precious little of it re: wild carnivores. If you don't believe me, do a little googling yourself. Here are some examples:
Coprophagia
http://en.wikipedia.org/wiki/Coprophagia#Coprophagia_in_animals"Capybara, rabbits, hamsters and other related species do not have a complex ruminant digestive system. Instead they extract more nutrition from grass by giving their food a second pass through the gut. Soft fecal pellets of partially digested food are excreted and generally consumed immediately. They also produce normal droppings, which are not eaten.
Young elephants, pandas, koalas, and hippos eat the feces of their mother to obtain the bacteria required to properly digest vegetation found on the savanna and in the jungle. When they are born, their intestines do not contain these bacteria (they are completely sterile). Without them, they would be unable to obtain any nutritional value from plants.
Gorillas eat their own feces and the feces of other gorillas. Similar behavior has also been observed among Chimpanzees. Such behavior may serve to improve absorption of vitamins or of nutritive elements made available from the re-ingestion of seeds. ...."
Whereas when domesticated dogs engage in
regular copraphagia, it seems to be viewed as an aberrant behavior, possibly "due to various medical problems." ("Owner Documentation of Coprophagia in the Canine,"
http://web.archive.org/web/20070427142031/http://www.vetmed.wsu.edu/pets/_archive/study.htm)
One common factor cited as reasons for regular coprophagia in both wild herbivores and domesticated dogs is diets deficient in certain nutrients that are plentiful and biovailable in meats, such as folate and B12 (cobalamin) (Handbook of behavior problems of the dog and cat, by Gary M. Landsberg; "COPROPHAGIA AND FEEDING,"
http://www.petngarden.com/dogs/dogs12.php). Is this just coincidence?
"Human faeces can contain significant B12. A study has shown that a group of Iranian vegans obtained adequate B12 from unwashed vegetables which had been fertilised with human manure. Faecal contamination of vegetables and other plant foods can make a significant contribution to dietary needs, particularly in areas where hygiene standards may be low. This may be responsible for the lack of aneamia due to B12 deficiency in vegan communities in developing countries." (Vitamin B12,
http://www.vegsoc.org/info/b12.html)
In the Middle-Ages, there were similiar oddball claims such as cures involving drinking vomit, snot etc. While I have a lot of respect for herbal medicine, I don't believe they got it always right, and indeed got it wrong a lot of the time re bloodletting and other "cures".
Yes, I think nearly everyone gets some things right and others wrong. I no of no one who gets everything right, including myself.